But you can legislate on whether to stop giving that country’s military the weapons it uses to violate any ceasefire orders and continue the genocide.

Actually, you’re right. There is literally nothing the US could do. Ignore these other people.

Israel only exists because of America’s support. They absolutely can legislate on that, they just choose to legislate for genocide.

If US stopped providing weapons and political cover for Israel then the atrocities would stop. US is a direct participant in the genocide.